1. Field of the Invention
The present invention relates generally to means for providing a source of print medium to an optical printer and, more particularly, to an apparatus and method for the insertion of such media cartridges into the printer and their subsequent removal.
2. Description of the Prior Art
Optical printers produce output by exposing photosensitive media. The photosensitive medium is typically housed in a light-proof cartridge to protect against inadvertent exposure. For example, an instant photographic film, such as that described in commonly-assigned U.S. Pat. No. 4,226,519, "Self-developing film pack with improved spread control structure," issued to Gervais et al., is housed in a substantially rectangular cartridge. Photographic cameras that accommodate such cartridges often use a hinged door-like mechanism to provide for the insertion and removal of the cartridge from the photographic camera. With such mechanisms, clearance is provided at the hinge to allow for the swinging of the door. Such a configuration, however, becomes awkward when adapted to a photographic printer. The printer may be intended for use while sitting on a worksurface or in the bay of a personal computer, where the location does not provide adequate clearance for a hinged door. Moreover, if the printer is intended for placement into a computer bay, it needs to be relatively small in size. A design suitable for use in a photographic camera, for example, might comprise gear trains and switching systems that extend substantially above the film plane and would not, therefore, be suitable for use in a standard computer bay.
Removal of the cartridge from the camera may be accomplished by pulling outward upon a plastic tab or other protrusion extending from the cartridge. This configuration may be practical when the door is able to swing open freely and the camera can be oriented so as to facilitate removal of the cartridge. However, it is not convenient for an optical printer, even a stand-alone printer.
It is desirable for an optical printer to include the ability to determine the speed of the film, a reliable ejection mechanism for exposed media, and means to indicate whether a film cartridge has been loaded into the printer. In conventional optical printers, separate systems are utilized to provide such features. However, such additional systems incur increased manufacturing costs and increase the likelihood of operational failures.
Accordingly, it is an object of this invention to provide an optical printer that can be adapted to fit into a standard computer bay.
It is another object of this invention to provide an optical printer that accepts film cartridges while requiring minimal clearance at the hinged door.
It is still another object of this invention to provide an optical printer that has a low profile gear train and switching system.
It is a further another object of this invention to provide a substantially unitary film speed gauging device and reliable ejection mechanism.